Simple map-like diagrams, known as T-O world maps, reflect a medieval European world view. These simple drawings portray the Earth's land masses as a circle surrounded by water.

The land is separated into three parts, demarcated by a T or a Tau cross, suggesting that Christ's head (or Jerusalem) was the center of the universe. The horizontal arms represent the Nile and Don Rivers, while the vertical arm is the Mediterranean. Oriented with East at the top, Asia occupies the top half of the circle, while Europe and Africa occupy the two bottom quarters. In addition, the continents are often, as in this example, identified with Noah's three sons -- Shem, Japeth, and Ham.

Originally conceived by Isidore, Bishop of Seville, in the early 7th century, such a diagram was included in his manuscript encyclopedia which was based primarily on classical authors, but also reflected the beginnings of Christian scholarship. Isidore's text and image were first printed in 1472. Shown here, is a version of the T-O diagram that appeared in the 1483 edition of Isidore's encyclopedia.